1. Field of the Invention
The invention relates to a mechanism for removing foreign matter for use in an electrophotographic printer.
2. Description of Related Art
FIG. 1 shows a conventional example of a foreign matter removing mechanism for an electrophotographic printer. As shown in FIG. 1, the foreign matter removing mechanism includes: a sheet guide 2 which is arranged in front of a photosensitive drum 1 in a sheet forward section and which has a smooth curved surface; and a foreign matter removing member 5 which confronts the sheet guide 2 and which defines such a narrow gap 4 as to allow a print sheet 3 to pass therethrough smoothly relative to the confronting surface.
As the print sheet 3 passes through the narrow gap 4 during printing, foreign matter 6 present on the print sheet 3 is dropped off by this narrow gap 4, thereby keeping the photosensitive drum 1 undamaged. In FIG. 1, reference numeral 7 designates a frame; 8, a retractor blade; 9, a tractor; and 10, a gap defined between the photosensitive drum 1 and the retractor blade 8.
In the conventional foreign matter removing mechanism including the sheet guide 2 and the foreign matter removing member 5, the confronting surfaces are designed to be curved. This allows the foreign matter 6 to pass therebetween without much resistance and, as a result, the foreign matter 6 loosely present or firmly stuck on the print sheet 3 cannot be removed sufficiently, damaging the photosensitive drum surface in some cases.